Injection equipment used in high-pressure injection and mixing method, high-pressure injection and mixing method

Abstract

To provide an injection apparatus which is free from restriction on increase in a nozzle size, enables easy structural design of a flow channel and has good fluid energy efficiency, and can improve construction efficiency of a high-pressure injection and agitation method.SOLUTION: An injection apparatus has a lower stage injection nozzle 21 of a curable material, and an upper stage injection nozzle 22 for compression air or high-pressure water are arranged at upper and lower parts of an apparatus side face. The lower stage injection nozzle 21 and the upper stage injection nozzle 22 are provided so that a vertical arrangement interval of the nozzles 21 and 22 is set at 34 mm and each of the nozzles has an angle of 2°, for example, so that jet flows are merged at a point of 500 mm from an apparatus center. For example, in construction in which general soil is regarded as an object ground, both fluids are integrated with each other by a negative pressure generated from a curable material jet which is jetted from the lower stage injection nozzle 21 and has large specific gravity, and destructive force and cutting force of the ground are increased.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] This invention relates to an injection device (special monitor) used in a double-pipe two-way injection mixing method that enables high-speed, large-volume, ultra-high-pressure injection ground improvement, and to a high-pressure injection mixing method using this device. [Background technology]

[0002] High-pressure jet mixing is known as one type of ground improvement method. In this method, hardening material is sprayed at high pressure from a spraying device (special monitor) attached to the end of a rod, and the ground and hardening material are mixed and mixed while cutting the ground, creating a cylindrical improved body underground. An overview of the normal construction of the high-pressure jet mixing method is shown in Figure 3.

[0003] The injection device used in the conventional double-pipe high-pressure injection mixing method generally has air nozzles concentrically around the injection nozzle of the ultra-high-pressure hardening material. This means that the installation area of ​​the injection nozzle base located on the outer periphery of the cylindrical injection device is large, which creates a problem in that it places restrictions on enlarging the nozzle size.

[0004] Furthermore, in conventional injection devices that use a concentric nozzle arrangement, each flow path within the double pipe is concentrated at one nozzle, which creates the problem of restrictions on the structural design of the flow paths aimed at reducing fluid energy loss.

[0005] Furthermore, in the case of highly viscous ground, when it is difficult to cut the ground and discharge the sludge using the conventional high-pressure jet mixing method, the ground is cut using high-pressure water prior to the injection of the hardening material, a process known as pledgetting (see Figure 4), which increases the number of ground cutting steps and is therefore inefficient. Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, in view of the problems of the prior art described above, the object of the present invention is to provide an injection device that has no restrictions on enlarging the nozzle size, has a simple structural design for the flow path, has good fluid energy efficiency, and is capable of improving the construction efficiency of high-pressure injection and mixing methods, and a high-pressure injection and mixing method using the same. [Means for solving the problem]

[0007] This object is achieved by an injection device having a first injection nozzle for injecting a hardener and a second injection nozzle for injecting compressed air or high-pressure water, the first and second injection nozzles being arranged above and below the side of the injection device, and the first and second injection nozzles being arranged so that the two jets meet at a point a predetermined distance horizontally from the side of the injection device.

[0008] In the above-mentioned injection device, the first and second injection nozzles are arranged so that the jet of compressed air or high-pressure water injected from the second injection nozzle arranged in the upper stage is subjected to a suction action by the negative pressure generated by the hardener jet injected from the first injection nozzle arranged in the lower stage.

[0009] In addition, the above-mentioned objectives are achieved by a high-pressure injection mixing method in which high-pressure water is injected from a second injection nozzle located on the upper level to cut the highly viscous ground, and at the same time, the ground is stirred and mixed with a hardening material injected from a first injection nozzle located on the lower level, thereby creating a cylindrical improved body. [Effects of the Invention]

[0010] According to the present invention, it is possible to arrange the flow paths (the flow path for compressed air or high-pressure water and the flow path for hardener) in the double tubular part of the injection device in parallel, which results in improved energy efficiency of the fluid in the injection device. Furthermore, the improved energy efficiency makes it possible to carry out high-speed construction using the high-pressure injection mixing method. Furthermore, the high-speed construction makes it possible to reduce the amount of sludge discharged compared to conventional methods. Furthermore, the improved energy efficiency makes it possible to improve the diameter.

[0011] Furthermore, in highly viscous ground, the pre-jet effect can be achieved by simultaneously injecting hardening material from the lower jet nozzle and high-pressure water from the upper jet nozzle, thereby improving construction efficiency on highly viscous ground (see Figure 5). [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a cross-sectional view showing an injection device according to the present invention; [Figure 2] FIG. 2 is a cross-sectional view showing the state during injection (when creating an improved body) by the injection device of FIG. 1. [Figure 3] FIG. 1 is a process diagram showing an example of normal construction using a high-pressure jet mixing method. [Figure 4] FIG. 1 is a process diagram showing an example of a high-pressure jet mixing method in combination with a pledget. [Figure 5] 1 is a process diagram showing an example of a high-pressure injection stirring method according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0013] (Configuration of injection device) First, the configuration of the injection device according to the present invention will be described with reference to FIGS.

[0014] The injection device 1 is a special monitor used in a double-pipe two-way injection mixing method. This spray device 1 has a set of upper and lower two-tiered spray nozzles (spray nozzles 21, 22), and two sets of upper and lower two-tiered spray nozzles are provided to enable bidirectional spraying. In addition, the spray device 1 is configured so that it can be attached to the tip of a double-tube rod, and has a double-tube flow path structure. The configuration of the spray device will be specifically described below.

[0015] As shown in FIG. 1, the injection device 1 includes: a lower stage injection nozzle 21 (first injection nozzle) for injecting a hardening material; an upper stage injection nozzle 22 (second injection nozzle) that injects compressed air or high-pressure water; A flow path 31 (first flow path) for a lower injection nozzle that is connected to the inner flow path of the double-tube rod; A flow path 32 (second flow path) for the upper stage injection nozzle that is connected to the outer flow path of the double-tube rod It has.

[0016] The upper and lower jet nozzles 21, 22 are nozzles that are separate and independent from each other, and are arranged above and below on the side of the jet device as shown in Figure 1. The upper and lower jet nozzles 21, 22 are also provided on separate and independent (separate) nozzle stands 41, 42. The nozzle stand 41 is a nozzle stand dedicated to the lower jet nozzle 21, and the nozzle stand 42 is a nozzle stand dedicated to the upper jet nozzle 22.

[0017] The hardening material is pumped through the inner flow path of the double-tube rod (the inner tube of the double-tube rod), and then passes through the flow path 31 of the injection device 1 and is injected from the lower injection nozzle 21.

[0018] Compressed air or high-pressure water is pumped through the outer flow path of the double-tube rod (the outer tube of the double-tube rod), and then passes through the flow path 32 of the injection device 1 to be injected from the upper injection nozzle 22.

[0019] In addition, in the injection device used in the conventional double pipe construction method, the injection nozzle for compressed air is arranged concentrically around the injection nozzle for the hardener, so that the high-pressure air forms a jet of fluid that concentrically surrounds the hardener jet, but this invention is completely different from this. That is, in the present invention, the nozzle 22 that sprays compressed air or high-pressure water is not provided concentrically with the nozzle 21 that sprays the hardener, nor is the compressed air or high-pressure water sprayed so as to surround the hardener jet. Therefore, in the present invention, it is not necessary to arrange the upper-stage jet nozzle 22 in close proximity to the lower-stage jet nozzle 21, and the upper and lower jet nozzles 21, 22 can be arranged separately. Furthermore, by separating the upper and lower jet nozzles 21, 22, it becomes easier to enlarge each nozzle. Furthermore, because the concentric nozzle arrangement seen in the prior art is not adopted, it is possible to make the flow paths 31, 32 leading to the upper and lower jet nozzles 21, 22 completely parallel, which improves the effect of reducing fluid energy loss within the device.

[0020] 2, in the present invention, the upper and lower injection nozzles 21, 22 are arranged so that the jets from each nozzle meet at a point (a predetermined point) that is a predetermined distance away in the horizontal direction from the side of the injection device. In FIG. 2, the central axis of the jet from each nozzle is indicated by a dashed line. In the embodiment shown in FIG. 2, as an example, the nozzles 21, 22 are arranged with a vertical spacing of 34 mm and at an angle of 2° so that the axes of the two jets meet at a point 500 mm from the center of the injection device.

[0021] 2, the injection directions of both injection nozzles 21 and 22 are inclined, but it is also possible to incline only one of them and inject the other horizontally. Also, the dimensions and specifications shown in FIG. 2 are merely examples, and the features of the injection device of the present invention are not limited to these.

[0022] (Functional effects of the injection device in the high-pressure injection mixing method) Next, the function and operation of the injection device according to the present invention will be specifically described with reference to FIG.

[0023] In the high-pressure injection mixing method using the injection device 1, first, a construction machine is set up at the center of the construction position of the ground improvement body, and a double-tube rod with an injection device attached to its tip is hung by a crane and attached to the construction machine. Then, while drilling water is being discharged from the injection device at the tip of the double-tube rod, the double-tube rod is rotated by the construction machine and inserted into the ground to the planned depth.

[0024] Then, when the double-tube rod equipped with the injection device reaches the planned depth, the double-tube rod is pulled up while being rotated. During the process of rotating and simultaneously pulling up the double-tube rod, compressed air (or high-pressure water) is sprayed from the upper-stage injection nozzle 22, and at the same time, hardening material is sprayed from the lower-stage injection nozzle 21. In this embodiment, two sets of upper and lower injection nozzles 21, 22 are provided, allowing for two-way injection.

[0025] As shown in FIG. 2, the compressed air (or high-pressure water) sprayed from the upper-stage jet nozzle 22 and the hardener jet sprayed from the lower-stage jet nozzle 21 join together at a point (predetermined point) a predetermined distance horizontally from the side of the spraying device to form a single integrated jet (jet fluid).

[0026] The fluid (compressed air or high-pressure water) to be injected from the upper-stage injection nozzle 22 is determined depending on, for example, the soil quality of the target ground. For example, if the soil quality of the target ground is ordinary soil, compressed air is selected as the fluid to be injected from the upper-stage injection nozzle 22, and if the target ground is highly viscous soil, high-pressure water is selected.

[0027] For example, in construction where the target ground is ordinary soil, the negative pressure (cavitation) caused by the hardening material jet with a high specific gravity sprayed from the lower spray nozzle 21 causes the compressed air from the upper spray nozzle 22 to be sucked in, and the formation of an integrated jet due to this interaction increases the destructive force and cutting distance of the ground, and the two-way spray makes it possible to perform large-diameter improvement work.

[0028] Furthermore, for example, when working on highly viscous ground, a pledget effect is achieved by simultaneously injecting hardening material from the lower jet nozzle 21 and injecting high-pressure water from the upper jet nozzle 22. That is, as the double-tube rod is rotated and pulled up, the high-viscosity ground is first excavated by the pledget effect of the high-pressure water from the upper jet nozzle 22. At the same time, the hardening material injected from the lower jet nozzle 21 stirs and mixes the ground, creating a cylindrical improved soil. Therefore, even in highly viscous ground, construction can be completed in just one step: pulling up the rod (see Figure 5). This eliminates the need for pledgets in an additional step prior to the injection of hardening material, as in the conventional technique shown in Figure 4. Thus, according to the present invention, the pledget for ground excavation and the injection of hardening material can be performed simultaneously, significantly improving construction efficiency compared to the conventional technique shown in Figure 4.

[0029] In this embodiment, ground improvement work for ordinary soil or highly viscous ground has been given as a specific example of the high-pressure injection mixing method using the injection device 1, but the applications of the present invention are not limited to this, and the present invention can be used, for example, to increase the bearing capacity of soft ground, to retain and stabilize excavated ground, to prevent water leakage from the ground, and to prevent ground liquefaction. [Explanation of symbols]

[0030] 1 Injector (special monitor) 21 Lower jet nozzle (first jet nozzle) 22 Upper jet nozzle (second jet nozzle) 31 Flow path for lower stage injection nozzle (first flow path) 32 Flow path for upper stage injection nozzle (second flow path) 41 Nozzle base for lower stage injection nozzle 42 Nozzle base for upper stage injection nozzle

Claims

1. a first injection nozzle for injecting a hardening material; a second injection nozzle for injecting compressed air or high-pressure water; the first and second injection nozzles are disposed above and below a side of the injection device; the first and second injection nozzles are provided so that the jets meet at a point horizontally spaced a predetermined distance from a side of the injection device; An injection device used in a high-pressure injection mixing method, characterized in that the jets from the first and second injection nozzles join together and form a single jet that cuts the ground.

2. The first and second injection nozzles are both tilted or one of them is arranged so that the jets from the first and second injection nozzles join together; The first jet nozzle located at the bottom jets a hardening agent having a higher specific gravity than compressed air or high-pressure water.

2. An injection device used in the high-pressure injection mixing method according to claim 1, wherein the first and second injection nozzles are arranged so that the jet of compressed air or high-pressure water injected from the second injection nozzle arranged in the upper stage is subjected to a suction action by the negative pressure generated from the hardener jet injected from the first injection nozzle arranged in the lower stage.

3. A high-pressure injection and stirring method using the injection device according to claim 1 or 2, A high-pressure injection mixing method characterized by cutting highly viscous ground with high-pressure water injected from a second injection nozzle located in an upper tier, while simultaneously stirring and mixing the ground with a hardening material injected from a first injection nozzle located in a lower tier, thereby creating a cylindrical improved body.

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